A strain gage is a device used to measure surface strains in structural materials. A type of strain gage most commonly used is an electrical resistance-type strain gage. An electrical resistance-type strain gage includes a metallic foil grid having a number of elongated, laterally-spaced, series-connected grid elements and enlarged terminal regions. The enlarged terminal regions may be attached to external electrical leads. In operation, as a structural material deforms, the foil grid elements change in length. This change in length results in a change in electrical resistance of the grid elements. The change in electrical resistance of the grid elements may be measured to provide a level of strain experienced by the structural material.
Using the strain gage to measure an amount of surface strain in a structural component usually requires securely affixing or bonding the strain gage to the structural component. The process of bonding the strain gage to the structural component usually requires chemically and mechanically preparing a location on the structural component to receive the strain gage, applying a masking material to the structural component to prevent subsequent process materials from migrating onto adjacent areas of the structural component, and bonding the strain gage to the structural component using cements and/or epoxies. Bonding materials may require mixing precise amounts of several different chemicals together and may require elevated temperatures and pressures while curing. After the bonding material has cured and an amount of strain has been measured, the strain gage may be either removed from the structural component, allowed to remain on the structural component, or the structural component may be discarded. If the strain gage is removed from the structural component, residual bonding material may also have to be removed from the structural component.
The above-described process of using a strain gage suffers several disadvantages. For example, the above-described process of applying the strain gage is complex and time-consuming. In addition, removing the strain gage from the structural component may damage the structural component and render the strain gage unusable for repeated use. Also, discarding the structural component or allowing the strain gage to remain on the structural component may be unacceptable alternatives.